This invention relates in general to diaphragms, and more particularly to a diaphragm whose frequency response may be changed by application of mechanical tension to the diaphragm.
A speaker, a microphone, a vibrator, or other similar electrical transducer device, typically comprises a diaphragm. The diaphragm, in such a device, normally oscillates as part of a vibrating transducer to convert electrical signals to mechanical motion or vice versa. As is well known by those of ordinary skill in the art, such electrical transducer devices are commonly found in communication devices, such as cellular phones, pagers, radios, and wireless communicators. Speakers typically convert electrical signals to audio output. Microphones normally convert audio input to electrical signals output. Vibrators are normally output devices that can provide a tactile signal to a user of a communication device. However, vibrators can additionally be input devices that convert mechanical vibrations to electrical signals. In all of these electrical transducer devices, the diaphragm is a key component. The frequency response of the diaphragm normally must be designed to match a particular application. Each application utilizes a specifically customized design for frequency response of a diaphragm.
The type of material used in the diaphragm typically provides a frequency response for the vibrating transducer. This material is selected by design for a particular application. In order to achieve broader frequency response for a diaphragm, normally after selecting a particular material, a mechanical adjustment is made to the diaphragm by changing a tension across the overall diaphragm. Traditionally, to change the tension of the diaphragm, a mechanical means, such as a motor or geared structure, varies a tension of a membrane in the diaphragm such as by varying a pulling force across the membrane. This changing of the tension of the membrane to customize (mechanically tune) a frequency response of the diaphragm for a particular application can be a complex, manually intensive, time consuming, and expensive process for a manufacturing technician.
Unfortunately, there are no standard ways to mechanically tune a diaphragm to match a desired frequency response. Consequently, a manufacturer of devices for different applications must inventory different diaphragms that have been individually customized for different frequency responses, as required by the different applications. This results in additional costs for maintaining an inventory of the different diaphragms.
Thus, there is a need for a more easily tunable diaphragm that can be easily customized for different applications.